Front to rear brake line replacement

[Drummerboy]

So today I decided to change out the blown rear rubber brake line on my '68 Chevy short bed. While doing so, I managed to brake the hard line thats on the back side of the frame. Pretty sure it was rusted and bad anyway.

My question is, should I just by a new, pre bent one from LMC, or build one? Also, besides a new clip set to hold the new line in place, what else should I buy and or replace?

[ourpobox]

If you buy pre-bent, the answer will be different...

... but, depending on where you start, you'll need the right length and diameter of line, and you'll need the right connectors on each end. Borrow a double crimping tool from the parts store and remember to put the connector on BEFORE you crimp the hose. :-)

That should be it unless I'm forgetting something. Seems like that is how I did it. Alternatively, you could get multiple lengths to make the run and do a union connector between them. Then they'll have the connectors already on the line...

[HO455]

If you go the make your own route I recommend using nickel copper tubing. It's easy to work with and can be polished if you want. If you need info on tubing sizes I have a write up on the job in my WMB thread below on page 8.

[nightrider388]

I ordered mine from Inline Tube. Told them what brake combo I was running and they sent me a complete kit. I went with stainless. It fit really good.

[BossHogg69]

Right Stuff Detailing has them too. I got my hardlines from Inline Tube and used Russell DOT rated SS flex lines in place of the rubber ones. Everything fit well.

[Drummerboy]

So the bad place on the hard line is just past the fitting. Would it be possible for me to just cut the bad place out, and use a compression fitting to run a new end on the hard line, back over to the rubber line?

[lolife99]

Some may disagree,... But NEVER use compression fittings for brake lines.
Standard double flare or AN fittings only.

Classic Tube is a good source also.

[Drummerboy]

Originally Posted by lolife99

Some may disagree,... But NEVER use compression fittings for brake lines.
Standard double flare or AN fittings only.

Classic Tube is a good source also.

Why not?

[AussieinNC]

Compression fittings are not suitable for the pressures involved in braking systems...and in your case, would likely fail when you tried to install them.

The fail when the tube being considered for a compression fitting is old and likely deteriorated both externally and internally.

Suggest you buy a pre bent line...if this is a daily driver, just use standard tube...

[Drummerboy]

Here's what I'm working with. The inside looks fine. Not sure why the photo is flipped upside down.

[AussieinNC]

There is no way that line will withstand a compression fitting...it will just collapse...

Save the heartache and possible brake loss and replace it and the other two metal lines on the rear end...

I would also be checking both of the front metal lines and rubber hoses...if the rear hose blew out, you can expect the front lines and hoses to be not that far from failing.

[AussieinNC]

Pic rotated

[AussieinNC]

LMC link

http://www.lmctruck.com/icatalog/cb/full.aspx?Page=148

[lolife99]

Originally Posted by Drummerboy

Why not?

Originally Posted by AussieinNC

Compression fittings are not suitable for the pressures involved in braking systems...and in your case, would likely fail when you tried to install them.

The fail when the tube being considered for a compression fitting is old and likely deteriorated both externally and internally.

Suggest you buy a pre bent line...if this is a daily driver, just use standard tube...

Exactly what he said?^^^

I would only do it in an emergency repair on the side of the road.
Never a permanent fix.

[Drummerboy]

I come up with this idea after talking to a local, reputable, mechanic, who may or may not be a member of this page. He said he's seen this plenty of times and suggested it. Now I'm seriously considering against it.

[Drummerboy]

Originally Posted by AussieinNC

Compression fittings are not suitable for the pressures involved in braking systems...and in your case, would likely fail when you tried to install them.

The fail when the tube being considered for a compression fitting is old and likely deteriorated both externally and internally.

Suggest you buy a pre bent line...if this is a daily driver, just use standard tube...

How difficult will it be to replace the whole line, sitting on jack stands in my driveway?

[AussieinNC]

The front to rear line is not that bad to replace,,,can sometimes be a PITA around the trans cross member.

There is a joiner fitting near the front cross member, passenger side, just follow the line inside the chassis rail ...

The two lines across the rear axle are ok to change...just take your time.

Remember to check the bleeder nipples on the rear cylinders...make sure they are free...can almost guarantee they will snap off...just looking at the chassis rust and the line rust...

LMC can also supply a clip set for the lines....the old ones always just snap off...I think its listed on that linked page I sent you.

[AussieinNC]

30-1725 is the clip set...

[Leftlane]

NAPA carries high pressure compression fittings, which in no way differ from any other hard line fitting in your braking system. They are hardened steel, not brass.
I've used them several times , and when done properly would have absolute confidence in them.
However, I would never...ever...use them to splice onto a signifigantly rusted existing line of questionable integrity.
Replace that line up until the next possible fitting or junction.
Replace all the rubber lines also if needed, since your bleeding anyway and they're relatively cheap.
I'd take a good hard look at the other 60ish year old hard lines as well.

[Drummerboy]

Great input guys, thank you! The only reason I'm having to replace the hard line I showed, is because I snapped it off while I was trying to replace just the blown rear rubber line. Had I know that I needed to hold the two fittings while replacing the one, I'd more than likely be driving the truck by now. Yes the hard line has surface rust, but I'm not seeing any rust though, especially considering that I'd been driving and so had the previous owner. But yes, there's always a possibility on any of these orginal lines could fail.

I'll by a new hard line from LMC and replace it. Can anyone tell me exactly where that line runs to and stops on the cab end?

[Leftlane]

You can go to Lmctruck.com an they have decent graphics with diagrams of all the component systems. If they sell the lines individually, just get what you need to the next junction.
Make sure you soak that next fitting with Kroil or PBBlaster for a couple days to saturate any rust prior to trying to loosening it. Work it back and forth while re-applying the solvent. Take your time, and use a backup wrench
.....

[AussieinNC]

The front to rear line has a joiner fitting on passenger side just behind the front cross member...

I would suggest you use two pipe flare wrenches, one on the joiner fitting and one on the pipe fitting on the rear line...otherwise you could twist the other front / rear line that runs across the cross member and up to the master cylinder.

If you order the new hard lines, the new one will give you an idea of where the joiner fitting is located...its usually behind the passenger front shock mount inside the chassis rail...see pic...take your time and use lots of spray lube...

[Drummerboy]

Originally Posted by AussieinNC

The front to rear line has a joiner fitting on passenger side just behind the front cross member...

I would suggest you use two pipe flare wrenches, one on the joiner fitting and one on the pipe fitting on the rear line...otherwise you could twist the other front / rear line that runs across the cross member and up to the master cylinder.

If you order the new hard lines, the new one will give you an idea of where the joiner fitting is located...its usually behind the passenger front shock mount inside the chassis rail...see pic...take your time and use lots of spray lube...

Sweet! I feel as if I'm ready to go into battle now.

[GRX]

Fab your own line if you can. Money you save can go into buying nickle/copper tubing. Easy to bend & flare. Only thing I use now.

Originally Posted by lolife99

Some may disagree,... But NEVER use compression fittings for brake lines.

x1,000. They are illegal in many states, including mine, for good reason.

[Drummerboy]

Well, I got the old line out and replaced, along with the new rear, rubber hose. Now I have the fittings on the front rubber lines marinating because they look pretty sketchy and upon the good advice from AussieinNC. I also have all of the bleeder valves soaking in oil as well.